When it comes to star quality, there are few who don't know the Grammy-winning songstress. When she wants to put her best foot—and physique—forward, she turns to the advice of her trainer, Pete Geracimo, who is a big fan of the SirtFood Diet.

Having trained with the likes of the British musician, Kate Middleton's famous sister Pippa Middleton and Sex and the City's Kim Cattrall, the health and fitness pro has a wildly recognizable roster of clients to his name. So, when he publicly praises a new way of approaching food, we listen.

Having been involved in the creation of Aidan Goggins and Glen Matten's SirtFood Diet, Geracimo promises "there is no one who will not benefit from following it," whether you have 15 Grammy Awards to your name or you reserve singing for the shower.

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The premise of the plan is simple—incorporate these foods in your diet and they will spark the body's ability to burn fat and your metabolism to ramp up.

According to the book, such foods were picked because of their high levels of sirtuin-activating nutrients. Sirtuins are proteins that activate processes deep in cells to increase metabolism, a result similarly ignited by fasting and exercise. The body contains seven different kinds of sirtuins, though SIRT1 and SIRT3 are considered the most important as, when activated together, play a large role in energy balance, the book says.

Sirtuins have also been found to increase the efficiency of muscles, reduce inflammation and repair damage in cells, according to Goggins and Matten. As for the foods themselves, we've all heard of them.

The diet highlights 20 SirtFoods, including arugula, red wine, cocoa, coffee, kale strawberries and walnuts, which, when consumed in the right quantity and form, can lead to pounds shed and more energy. The book features dozens more fruits, vegetables, nuts and seeds that also contain sirtuin-activating nutrients, but in lesser amounts.

The diet begins with the first seven-day phase, including three days of 1,000 calories and three days of 1,500 calories with juicing throughout. Once that is completed, those following the regimen move into a second phase, which marks a return to three main meals a day rich in SirtFoods in the hopes that readers will incorporate such foods in their diet for the rest of their lives.